In the present mobile telecommunication signal transceiving system, such as a wireless base station, a power amplifier is an indispensable component to improve the performance of signal transmitting. However, standards concerning structure and design of a power amplifier have long been unified in the power amplifier field. During R&D and manufacture of communication devices, communications device manufacturers always purchase power amplifiers manufactured by third-party manufacturers to reduce the costs of R&D and manufacture. Therefore, factors affecting the performance of power amplification are covered by the design of a circuit board and a structural component that bear the amplifier.
FIG. 1 is a structural schematic diagram of a communications device in the prior art. The communications device includes a power amplifier 1, a circuit board 2, and a structural component 3. The structural component 3 is made of an electrically conductive material and is grounded. The circuit board 2 is attached to the structural component 3. The power amplifier 1 is fixed on the structural component 3 by a slot 22 on the circuit board 2. Copper foil 24 is printed on the lower surface of the circuit board 2. The copper foil 24 is grounded through the structural component 3. Power amplification matching joints 23 made of an electrically conductive material are attached to both sides of the slot 22, and pins 12 on both sides of the power amplifier 1 are lapped on the power amplification matching joints 23 respectively.
During use, because the copper foil 24 is grounded, the power amplification matching joints 23 directly refer to the grounded copper foil 24 on the lower surface of the circuit board 2, and the part between the power amplification matching joints 23 and the copper foil 24 becomes an intermediate medium used by the power amplification matching joints 23 as a reference for impedance matching. Therefore, the circuit board 2 generally needs to use a high-frequency board with good impedance continuity and consistency and with less loss in high-frequency signals, to guarantee the stability of the power amplification effectiveness of the power amplifier 1 and to increase the operating efficiency of the power amplifier 1 as much as possible. But because high-frequency boards are expensive, the use of high-frequency boards will increase the costs of entire devices.
Therefore, a new device matching a power amplifier is required, so that without using a high-frequency board, the circuit board can still enable a power amplifier to have relatively stable power amplification effectiveness and relatively high operating efficiency.